Synchronous clock comprising a striking mechanism



Sept. 1, 1936. H. KINKHORS T 2,052,832

SYNCHRONOUS CLOCK COMPRISING A STRIKING MECHANISM Filed April 15, 1933 I nvenfi r: If. Kinkkora if,

Patented Sept. 1, 1936 UNITED STATES PATENT OFFICE SYNCHRONOUS CLOCK COMPRISING A STBIKING MECHANISM Application April 13, 1933, Serial No. 666,035 In the Netherlands April 18, 1932 2 Claims.

The present invention relates to a synchronous clock comprising a striking mechanism.

In the clocks driven electrically by means of a synchronous motor a spring is used for actuating the striking mechanism which spring after release is automatically wound up again by the motor. The clock is equipped with a number of separate wheels, levers and hammers forming the striking mechanism, which is operated at the 10 appropriate moments by the normal driving mechanism of the clock.

The main object of the invention 'is to simplify the construction of such clocks in order that they may be readily manufactured in large quantities.

With clocks according to the invention the striking mechanism is directly driven from the synchronous motor. In an embodiment according to the invention the wheels of the normal traversing gear or atleast some of them are simultaneously used for driving the striking mechanism so that the separate spring and wheels of the striking mechanism are dispensed with.

The principle underlying the invention holds 25 good for clocks comprising striking mechanisms of different type, of which those provided with a toothed quadrant and witha recessed disc respectively are generally known.

Constructions furnished with this type of strik- 30 ing mechanism will be described hereinafter.

With a suitable form of construction I of the invention, the minute wheel comprises two di. ametrically arranged pins cooperating with a lever 35 which on being moved by the pins lifts the ratchet lever, of the toothed quadrant or of the recessed disc thus releasing these members.

Hereinafter first of all a clock comprising a toothed quadrant striking mechanism will be considered. The pin wheel which cooperates with the toothed quadrant and by which the toothed quadrant is cause to resume its inoperative position upon striking of the clock is continuously driven from the motor shaft through a toothed 45 gearing. The driving wheel mounted on the shaft of the pin wheel may be provided with one or more pins cooperating with levers secured to the shaft ofthe hammer of the chiming mechanism. Furthermore, a second lever may be provided 59 which isturned upon releasing the tot-ed quad.-

' rant and by which the hammer is brought into its active position shortly thereafter. Preferably an arm of the second lever is provided with an oblique surface against which the hammer shaft is pressed 5; by means of a, spring.

After the toothed quadrant has been released the hammer shaft is displaced shortly thereafter against the action of a spring due to the movement' of the second lever. The levers for operating the hammer which are mounted on the shaft are actuated at each rotation of the pin wheel by the pins referred to of the toothed wheel mounted on the'shaft of the pin wheel. Y

As the pin wheels of synchronous clocks rotate continuously it might occur that the toothed quadrant, when a comparatively large part of the quadrant representing consequently a relatively large number of teeth must dropeach tooth usually corresponds to one strokeis prematurely caught by the pin wheel.

In order to avoid this drawback the periphery of the pin wheel may be furnished with an upstanding rim provided with one or more slits, whilst an elastic attachment is provided at the back of the toothed quadrant. This attachment, when the quadrant occupies its position of rest, lies between the pins of the pin whe'el'and the upstanding rim, consequently on the inner surface of the rim and moves through one of the slits upon disengaging the quadrant, thus always ensuring a sufiicient time required for dropping before the quadrant is caught by the next pin of the pin wheel. For this purpose the pins and the slits must be given the correct position with respect to each other.

The above description substantially relates to clocks comprising a toothed quadrant striking mechanism. In the case of clocks having a striking mechanism comprising a recessed disc, a lever may be provided which is driven from the minute wheel and which 'on being moved relieves the recessed disc thus couplingthe latter with the traversing" gear by means of a coupling operated by said lever, which coupling preferably consists of a ratchet wheel witha pawl.

The invention will be more clearly understood by reference to the accompanying drawing representing by way of eXample,'some forms of construction' thereof. 1

Fig. l is a front view of partof the clockwork mechanism of a synchronous clock having a striking mechanism.

Fig. 2 is a side view of this part and Fig. 3 is a plan view thereof.

Referring to the drawing, the driving mechanism is arranged in a known manner between the frame parts I of the clock and comprises a synchronous motor 2 which drives the hour hand 3 of the clock through the intermediary of a toothed gearing. For the sake of clearness the detailed construction of the driving mechanism between the motor and the hands has not been shown on the drawing. The minute wheel 4 is provided with two diametrically arranged pins 5 operating a'lever 6 pivotally secured to the front part of the frame whereby lever 6 is reciprocated twice during each rotation of the wheel 4. OW- ing to this movement of lever 6, the end of arm 9 lifts a ratchet lever I thus disengaging a pin 24 from the teeth of a toothed quadrant 8 and allowing the quadrant to fall in a known manner over a. given distance. As is well known this distance is controlled by the usual snail cam which is usually connected to the shaft of the hour hand. Thereupon the quadrant 8 is caused to resume its initial position by the pin wheel I during which movement the clock strikes the appropriate number of hours. The pin wheel I0 is constantly driven from the motor shaft through the intermediary of a toothed gearing. The wheel II of this toothed gearing is secured to the shaft of the pin wheel and is provided with one or more pins I2 which'are brought into engagement with a lever I secured to the shaft I3 of the hammer I4 ofthe striking mechanism when the shaft I3 is moved into a position in which lever I5 lies in the path of the pins I2.

To the front side of the front part of the frame is secured a second pivoted lever I6 which, after release of the quadrant 8, is turned clockwise so as to enable the displacement of the shaft I3 of the hammer mechanism.

For: this purpose the lever I6 is provided with an arm I'I having an oblique end surface I8 which bears against an end of the shaft I3 passing through the frame wall. Upon clockwise movement of the lever I6 after release of the quadrant the shaft I3 is moved forwardly by the action of a spring I9 bearing on the back part of the frame, so that the lever I5 enters into the path of the pins I2 of the toothed wheel II. The hammer I4 is thereby lifted a few times in accordance with the number of teeth over which the quadrant 8 falls. The periphery of pin wheel I0 is provided with an upstanding rim 20 normal to the plane of the disc to which the pins 26 are secured. In the form of construction represented in the drawing the rim is provided with two diametrically arranged slits 2|. From the back of the quadrant 8 an elastic pin 22 projects'within the rim 20 of the pin wheel I0. After disengagement of the quadrant 8 the pin 22 moves through one of the slits 2|, whereupon the quadrant falls over the determined distance. The slits 2| are provided directly behind the pins 26 in the direction of rotation of the pinwheel I0 so that after pin 22 has passed through the slit 2| it takes as long as possible before the next pin 26 engages the teethof the quadrant.

In order to disengage the hammer mechanism when the quadrant 8 is returned to its upper position shown in Fig. l, the shaft I3 must be displaced against the action of the spring I9. For this purpose the lever I6 is connected to the quadrant'8 through a rod 23 (see Figs. 1 and 2). At the end of the movement of the quadrant the rod moves the lever I6 counterclockwise, whereby the surface I8 moves over the end of the shaft I 3, and moves same in axial direction against spring I9.

Inthe operation of the device, assuming the partsto be in the position shown in Fig. 1, one of the pins 5 of the minute wheel 4 will engage the'end of arm 21 and rotate lever 6 counterclockwise whereby the end of arm 9 will disengage, from the teeth of quadrant 8, the pin 24 secured to lever I. Disengagement of pin 24 allows the quadrant 8 to fall down through a distance depending upon the number of strokes to be made, as soon as one of the slits 2| comes into the proper position to allow the pin 22 to pass therethrough. V

The lever'I remains in its upper position with pin 24 disengaged from the teeth of quadrant 8 as long as arm 21 is held up by pin 5. As long as the pin 24 is out of engagement with the teeth of the rack, quadrant 8 will drop each time it is raised in one tooth by the pins 26 of constantly rotating pin wheel ID, as a result of which the quadrant 8 will not be raised out of its lower position.

Furthermore, as long as arm 21 is held in its upper position by one of the pins 5, it remains in contact with'the bottom of an extension 25 of lever I6 whereby movement of arm 11 in a clockwise direction and actuation of the hammer mechanism is prevented. A short time afterwards and while quadrant 8 is still in its lower positionarm 21 is set free from pin.5, whereby lever 6 due to its own weight turns clockwise and arm 21 releases its support of lever I6 at the extension 25. During the clockwise movement of lever 6, arm 21 comes in contact with an out-.

enters the path of pins I2 and the hammer mechanism is operated thereby.

When arm 21 leaves pin 5, lever I falls intoit lower or ratcheting position whereby the quadrant 8 will be raised in one tooth increments by. the pins 26 of pin wheel I 0. As the quadrant-v 8 reaches its original upper position (as shown in Fig. 1) it rotates lever I6 counterclockwise by means of rod 23, whereby the oblique surface portion I8 moves shaft I3 axially against the compression of spring I9 so as to remove arm|5 from the path of pins I2; thus making the striking mechanism inoperative. The number of strokes will be determined by the distance through which the quadrant has fallen and is controlled by a snail cam in known manner.

It is evident that many variations of the construction of the device set out hereinbefore are possible with-out departing from the spirit of the invention. It is possible, for instance, to arrange the frame parts I at a'smaller distance from each other, in which case the synchronous motor is placed behind the back part of the frame. Owing. to this the depth of the clockwork is reduced.

What I claim is:

1. In an electric clock having hands; an electric driving motor; driving gearing between said motor and hands; and a striking mechanism; said striking mechanism comprising a rack, a pawl member to restrain the movement of said rack, a lever actuated by said driving gearing at predetermined intervals to. make said member inoperative and to allow the rack to fall from its normal positionand to make said rack operative again, a snail cam associated with the hour hand of the clock to limit the fall'of said rack, a pin wheel directly driven from said driving gearing to return the rack to its normal position, a wheel driven from the driving gearing and provided with a plurality of pins, a hammer mechanism comprising an axially slidable mem-' her having an arm thereon, a spring acting on said slidable member to move said arm into the path of said pins, and means actuated by said lever after said pawl member has been made operative again to allow said arm to be moved into the path of said pins during the time the rack is being returned to its normal position, said means being made inoperative by the rack when the rack reaches its normal position.

2. In an electric clock having hands; an electric driving motor; driving gearing between said motor and hands; and a striking mechanism; said mechanism comprising a hammer mechanism, a rack having a projection thereon, a memher to restrain the movement of said rack, a lever actuated by said driving' gearing at predetermined intervals to make said member inoperative and to make said member operative again, a pin wheel constantly driven from the driving gearing to return the rack to its normal position and having an annular cam provided with two slits, said cam and slits acting on said projection to allow said rack to fall at predetermined intervals, a snail cam associated with the hour hand of the clock to limit the fall of said rack, and means actuated by said lever after said member has been made operative again to couple the hammer mechanism directly with the driving gearing during the time the rack is being returned to its normal position, said means being made inoperative by the rack when the rack reaches its normal position.

HENDRIK KINKHORST. 

